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mb_check_encoding

(PHP 4 >= 4.4.3, PHP 5 >= 5.1.3, PHP 7, PHP 8)

mb_check_encoding — Check if strings are valid for the specified encoding

Description

mb_check_encoding(array|string|null $value = null, ?string $encoding = null): bool

Checks if the specified byte stream is valid for the specified encoding. If value is of type array, all keys and values are validated recursively. It is useful to prevent so-called "Invalid Encoding Attack".

Parameters

value

The byte stream or array to check. If it is omitted, this function checks all the input from the beginning of the request.

Warning

As of PHP 8.1.0, omitting this parameter or passing null is deprecated.

encoding

The expected encoding.

Return Values

Returns true on success or false on failure.

Changelog

Version Description
8.1.0 Calling this function with null as value or without argument is deprecated.
8.0.0 value and encoding are nullable now.
7.2.0 This function now also accepts an array as value. Formerly, only strings have been supported.

© 1997–2025 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.mb-check-encoding.php